Genital HPV infection is one of the most commonly diagnosed STIs worldwide and its high prevalence may also contribute to increased HIV transmission risk. Although HPV infection has been causally linked with chronic disease sequelae both in men and women, relatively little is known about the distribution of HPV infection and HPV subtypes among in relation to HIV status. Understanding the prevalence, distribution, and general sources of HPV subtypes among both HIV+ and HIV- individuals is important for understanding long term health consequences of HPV. Researchers within the Center for Research on Global Health at the School of Public Health, Medical Sciences Campus, Puerto Rico, in collaboration with the largest publicly funded STI clinic on the island (Centro Latinoamericano de Enfermedades de Transmisi[unreadable]n Sexual (CLETS)), are conducting an assessment of drug and sexual risk among sexually active, young male drug users. Using an ethnoepidemiological approach that integrates behavioral research and molecular epidemiology, with the study has the following research objectives: 1. Prevalence: To compare the prevalence of anogenital HPV infection in a clinic-based sample of HIV+ and HIV- young male drug users in Puerto Rico. 2. Genotype Variability: To compare the distribution of HPV subtypes in a clinicbased sample of HIV+ and HIV- young male drug users in Puerto Rico. 3. Sexual Risk Factors: To compare HIV+ and HIV- young male drug users, with particular attention to sexual risk practices (e.g., sexual practices, sex partnering) that may be associated with HPV subtypes and/or HIV/HPV coinfection.